With regards to using the search term to see if a thread already exists, that is to look for a thread to see if your question is answered already. The problem with using a 3 month old thread (which hasn't been posted on for as long) is that a lot of the original issues won't be relevant, particularly here.
If a thread is still relevant it's not grave bumping, if it's just being 'bumped' to keep Chewy from eating it even though the discussion has ended, that's just taking up valuable space for more relevant threads.
To be honest if there's a thread which hasn't been posted on for 3 months, it probably isn't going to have any discussion left in it.
18-Oct-2013 09:01:51